Fluid pressure control valve



IN VEN TOR.

M. B. CONRAD ETAL FLUID PRESSURE CONTROL VALVE:

Filed Jan. 3o, 195e Sept. 13, 1960 United States Patented Sept. 13, 1960 FLUID PRESSURE CONTROL VALVE Martin B. Conrad and Earnest H. Clark, Jr., Downey, Calif., assignors to Ealrer Oil Tools, Inc., Los Angeles, Calif., a corporation of California Filed Jan. 30, 1956, Ser. No. 562,287

9 Claims.. (Cl. 251-348) The present invention relates to valve devices, and more particularly to subsurface valve mechanisms adapted to be lowered in well bores for the purpose of controlling the ilow of fluids therewithin.

`Certain operations must be performed in well bores containing gas under pressure without killing the well, as by loading it with drilling mud or other weighted liquids. These operations include the use of tubular strings, such as drill pipe or tubing, through which the gas would be conducted to the top of the hole, creating a hazardous condition, unless the gas were prevented from ilowing up through the tubular string.

The present invention is concerned with improved valve apparatus for closing the tubular string while it is being run in or out of the hole, to prevent gas or other fluids from llowing through the tubular string to the `top of the hole, the apparatus being easily opened whenever desired, to permit passage of fluids in either direction through the tubular string.

Another object of the invention is .to provide a Valve apparatus of the character indicated, in which fluid pressure in the well bore externally of the apparatus tends to maintain the valve in closed position, the valve, nevertheless, being easily opened whenever its open condition is required. The valve apparatus is such as to have a full and unrestricted passage through it when it has been placed in a fully open condition.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of a form in which it may be embodied. This form is shown in the drawings accompanying and forming part of the present speciiication. It will now be described in detail, for the purpose of illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

Referring to the drawings:

Figure l is a longitudinal section through a valve apparatus embodying the invention, the valve being shown in open condition;

Fig, 2 is a view similar to Fig. l, the valve being disposed in its fully closed position;

Fig. 3 is a cross-section taken along the line 3 3 on Fig. l;

Fig. 4 is a cross-section taken along the line 4 4 on Fig. l.

As disclosed in the drawings, it is desirable to permit or prevent liuids from passing through a tubular string A extending to the top of the well bore, by providing a valve apparatus B secured to the lower end of the tubular string and also to a well tool therebelow (not shown), such as a well packer.

The valve apparatus B includes an outer housing structure telescopically disposed over an inner structure or mandrel 11.` Relative longitudinal movement between the housing and mandrel will determine the open or closed condition of the valve apparatus. As specifically shown,

the outer housing 10 includes an upper head 12 having a threaded box 13 for threadedly securing the housing to the lower end of the tubular string A. This head 12 is threaded into an intermediate housing section 14, the lower end of which is threaded into a lower housing section 15 having an inwardly directed ilange and spring seat 16.

The tubular mandrel 11 has a transverse valve seat 17 at its upper end adapted to be engaged by a iiapper valve head 18 which is pivotally mounted on :a pivot or hinge pin 19 secured to an arm 20 welded to or otherwise suitably attached to the upper portion of the mandrel. The valve head 18 can swing from its open, longitudinal position, disclosed in Fig. l, downwardly to a transverse position in engagement with the valve seat 17, to close the passage 21 through the mandrel. T o prevent leakage between the valve head and valve seat, the former has an annular seal ring 22, made of rubber or rubber-like material, disposed in its forward or sealing face 23, which is adapted to engage the end or valve seat 17 of the mandrel. The seal 22 engages such end face 17 outwardly of the inner surface 24 of the mandrel, as explained hereinbelow.

The valve head 18 is shiftable from its position in sealing engagement with the valve seat 17 to its fully open position in a positive manner by a holding and actuating sleeve 25 which is connected to the housing 10. As specifically shown, the holding and actuating sleeve 25 has an upper peripheral groove 26 receiving an inwardly directed ilange 27 of a two-piece coupling ring 28 which has an upper inwardly directed flange 29 received within a peripheral groove 30 in the lower portion of the housing head 12. The coupling ring 28 has an externaldiameter conforming to the internal diameter of the intermediate housing section 14, so as to prevent displacement of the coupling ring from the companion grooves 30, 26 in the head 12 and the holding and actuating sleeve 25. It is evident that the coupling ring 28 secures the sleeve 25 to the upper housing head 12 against longitudinal movement. Rotary motion between the housing head and the sleeve is prevented by a pair of diametrically opposed longitudinally extending dowel pins 31 secured thereto. The coupling ring 28 and the dowel pins 31 cause the holding sleeve 25 and housing 10 to move together in all directions as a unit.

The holding sleeve 25 has an intermediate inclined cam surface 32 adapted to engage the outer marginal portion of the sealing face 23 of the valve head 18, and thereby shift it laterally to its fully open position. These inclined cam faces or surfaces 32 merge into holding surfaces 33 extending substantially parallel to the axis of the apparatus, which are also engageable with the same marginal portions of the valve head to hold it in a fully open position displaced completely to one side of the central passage 21 through the mandrel 11, holding an actuating sleeve 25, and upper housing head 12. Such passage 21 preferably has a diameter at least equal to the inside diameter through the tubular string A, to provide an unobstructed and fully open passage for the flow of Huid in either direction through the valve apparatus B. The inside diameter of the holding sleeve 25, with the exception of its uppermost portion, Ais greater than the external diameter of the upper portion 34 of the mandrel 11, to permit such upper portion to shift upwardly and downwardly within the sleeve 25 in obtaining the shifting of the valve head 18 into and out of engagement with its companion seat 17.

The valve head 18` is maintained properly oriented with respect to the cam and holding surfaces 32, 33 by an arm or key 35 welded, or otherwise suitably secured, to the upper portion 34 of the mandrel and disposed within a longitudinal slot `or keyway 36 in the holding and actuating sleeve 25. This sleeve is separated into two parts from its lower end to its upper portion, where the two parts are held together by means of a bridge piece 37 integral with the two halves of the sleeve. This bridge piece 37 terminates in a plane that is common to a downwardly directed shoulder or backing surface 33 on the sleeve 25, which is adapted to engage the rear face 39 of the apper valve head 18, to hold the latter in sealing engagement with its companion valve seat 17.

When the housing occupies an extended position with respect to the mandrel 11, such as disclosed in Fig. 1, the valve head 18 is in engagement with the holding surfaces 33, yor in a fully open position. Such relative position between the housing 10 and the mandrel 11 is positively determined by engagement of a stop flange 40 on the mandrel 11 with a companion inwardly directed flange or shoulder 41 at the lower portion of the intermediate housing section 14, and which is slidably engageable with the periphery 42 of the mandrel below the flange 40. Upon relative downward movement of the housing 10 with respect to the mandrel 11, the holding and actuating sleeve 25 is shifted downwardly over the upper portion 34 of the mandrel, the valve seat 17 being disposed above the cam surfaces 32, which permits the valve head 18 to swing down into engagement with its valve seat 17, whereupon a small additional downward movement of the housing 10 relative to the mandrel 11 will bring the backing surface or shoulder 38 of the holding sleeve 2S against the rear face 39 of lthe flapper valve head 18, in eiect, clamping the flapper valve head 18 between the backing surface 39 and the valve seat 17.

Leakage of uid between the housing 10 and mandrel 11 in a downward direction is prevented by a suitable side seal ring 4S, such as a rubber 0 ring, disposed in an internal groove 46 in the intermediate housing ange 41 and slidably and sealingly engaging the periphery 42 of the mandrel below the mandrel stop flange 40. Leakage of uid in an upward direction from the housing can be prevented by a thread seal between the housing head 12 and the intermediate housing section 14. This seal is specifically disclosed as being constituted by a seal ring '47, such as a rubber O ring, disposed in a peripheral groove 48 in the upper housing head 12 and engaging the inner wall of the intermediate housing section 14.

The valve apparatus B is normally urged to a closed condition by ya helical compression spring 49 disposed within the lower housing section around the mandrel 11. The lower end -of this spring bears against the lower flange and spring seat 16 of the lower housing section, its upper end bearing against a spring seat 50r coupled to the mandrel 11 by engaging a two-piece ring 51 disposed within a peripheral groove 52 in the mandrel, the ring being prevented from moving out of the groove by being encompassed by the upper portion 53 of the spring seat 50. It is evident that the compression spring 49 tends to shift the mandrel 11 relatively in an upward position within the housing 10, permitting the dapper valve head 18 to swing downwardly into engagement with its seat 17, to be clamped against the backing or holding surface 38 of the actuating sleeve 25. Thus, the valve device will normally occupy a closed position, but it can be opened against the force of the spring 49 by relatively elevating the housing 111 with respect to the mandrel 11, which will cause the cam surfaces 32 to swing the apper valve head 18 completely to one side of the housing and to a fully open position, where the apper valve head will be held by the holding surfaces 33 of the actuating sleeve 25.

The maintenance of the valve in a closed condition is also secured by thev fluid pressure in the well bore externally of the valve apparatus. Assuming the valve to be in its closed position, such as shown in Fig. 2, the lluid pressure externally of the apparatus is acting in an upward direction on the mandrel 11 over the area R, which is the annular area between its internal and external surfaces 24, y42. Suchr uid pressure is tending to shift the mandrel upwardly to press its valve seat 17 against the valve head 18 and the seal ring 22 in the latter, forcing the valve head against the backing surface 38. In other words, the fluid pressure acting upwardly on the mandrel 11 is tending to hold the valve head 18 in its closed position clamped between the backing surface 38 on the sleeve 25 and the valve seat 17. The iluid pressure externally of the mandrel can also pass to its interior, but it can only act in a downward direction on the mandrel over the annular area S, which is the area between the inner surface 24 of the mandrel and the sealing circle 611 of the seal ring 22 against the valve seat 17. From an inspection of the drawings, it is evident that the area S is slightly less than the area R, so that the uid pressure externally of the apparatus is acting on the mandrel 11 over a resultant area tending to hold the mandrel in its upward position within the housing 10, which is the position in which the valve head 18 is held in clamped relation between the valve seat 17 and the backing surface 38.

The area R is preferably only made slightly greater than the area S, to require only a relatively small force to overcome the external fluid pressure, as well as the force of the spring 49, in shifting the valve to open position upon the taking of an upward pull on the housing 10. For example, if the differential area of R minus S is one square inch, and the fluid pressure externally of the valve apparatus and internally of the mandrel is 1,000 p.s.i., then it would only be necessary to exert a pull of 1,000 lbs. to overcome the fluid pressure, plus an additional pull corresponding to the closing force exerted by the spring 49, which might be of the order of 300 to 600 lbs., making a total pull of 1,300 .to 1,600 lbs. Such pull can be easily exerted when the apparatus is inthe well bore.

In one use of the apparatus, it is desired to run the tubing string A in a hole that has gas under pressure without killing the producing formation. The tubular string is to be secured to a lower tool (not shown) in the well bore, such as a well packer which may already be anchored in packed-olf condition in a well casing (not shown). apparatus B connected to its lower end, is vinserted in the well bore or well casing, its apper valve 18 is in the closed condition shown in Fig. 2, to which position it has been urged by the compression spring 49. In view of the pressure in the well casing, the valve will remain in closed condition, since the pressure tends to maintain the mandrel 11 in its upper telescoped position within the housing 18. The valve apparatus is suitably secured to the lower tool, such as the well packer already anchored in the well casing, in any known manner, as by latching it into the latter. Longitudinal movement of the mandrel 11 is thereby prevented, permitting an upward pull to be taken on the tubular string A, which will shift the housing 10 upwardly against the force of the spring 49 and against the force of the fluid pressure acting over the differential area R minus S, to cause the cam surfaces 32 to cam the valve head 18 to its fully open position shown in Fig. 1, the extent of relative upward movement being limited by engagement of the internal flange 41 of the housing with the stop flange 40 on the mandrel 11. With the valve in the fully open position, its passage 21 is clear and unobstructed. Fluent materials can then be pumped down the tubular string and through the valve for passage through the lower packer (not shown) and for discharge into the well bore, to accomplish the desired purpose or purposes therewithin.

After the operation in the ywell bore has been completed, the valve apparatus B may be disconnected from the lower packer (in a known manner), the spring 49 then shifting the mandrel 11 relatively upward in the housing 1) to place the flapper valve 18 in its closed condition once again, such as shown in Fig. 2, whereupon any pressure in the well bore or well casing will assist in When the tubular string A, with the valve .fassa-rss holding the valve in its closed condition as the tubing string is elevated in the well bore. In this manner, any lluid pressure, such as gas under pressure in the Well bore, is prevented from flowing upwardly through the tubing string A to the top of the hole.

The inventors claim:

1. In a valve apparatus adapted to be incorporated in a tubular string to be disposed in a well bore: inner and outer tubular members telescopically arranged with respect to each other; a valve seat on said inner member communicating with the interior of said inner member; a valve element carried by said inner member and movable relative thereto into and out of engagement with said seat; means on said outer member engageable with said valve element in response to relative telescopic movement between said members to shift said Valve element with respect to said seat; holding means on said outer member engageable with said valve element to hold said valve element engaged with said seat; said inner member being imperforate throughout the length of its portion which is telescoped within said outer member; seal means between the exterior of said inner member and outer member and engaging said members to prevent leakage therebetween; the annular area of said inner member between its inner surface and its sealing diameter with said outer member being slightly greater than the annular area of said valve seat between the inner surface of said inner member and the sealing circumference of said valve element with said seat.

2. in a valve apparatus adapted to be incorporated in a tubular string to be disposed in a well bore: inner and outer tubular members telescopically arranged with respect to each other; a valve seat on said inner member communicating with the interior of said inner member; a valve element carried by said inner member and movable relative thereto into and out of engagement with said seat; means on said outer member engageable with said valve element in response to relative telescopic movement between said members to shift said valve element with respect to said seat; means for holding said valve element in engagement with said seat; said inner member being imperforate throughout the length of its portion which is telescoped within said outer member; seal means between the exterior of said inner member and outer member and engaging said members to prevent leakage therebetween; the annular area of said inner member between its inner surface and its sealing diameter with said outer member being slightly greater than the annular area of said valve seat between the inner surface of said inner member and the sealing circumference of said valve element with said seat.

3. In a valve apparatus adapted to be incorporated in a tubular string to be disposed in a well bore: inner and outer tubular members telescopically arranged with respect to each other; a valve seat on said inner member communicating with the interior of said inner member; -a valve element carried by said inner member and movable relative thereto into and out of engagement with said seat; means on said outer member engageable with said valve element in response to relative telescopic movement between :said members to shift said valve element with respect to said seat; holding means on said outer member engageable with said valve element to hold said valve element engaged with said seat; said inner member being imperforate throughout the length of its portion which -is telescoped within said outer member; seal means between the exterior of said inner member and outer member and engaging said members to prevent leakage therebetween; the annular area of said inner member between its inner surface and its sealing diameter with said outer member being slightly greater than the annular area of said valve seat between the inner surface of said inner member and the sealing circumference of said valve element with said seat; and spring means between and acting on said tubular members to shift said tubular members longitudinally with respect to each other to a position in which said holding means holds said valve element engaged with said seat.

4. In a valve apparatus adapted to be incorporated in a tubular string to be disposed in a well bore: an upper, outer tubular member; a lower, inner tubular member telescoped within said outer member; an annular valve seat on the upper end of said inner member communicating with the interior of said inner member; a valve element carried by said inner member and movable relative thereto into and out of engagement with said seat; means on said outer member engageable with said valve element in response to upward movement of said outer member with respect to said inner member to shift said valve element out of engagement with said seat; holding means on said outer member engageable with said valve element to hold said valve element engaged with its seat upon downward movement of said outer member with respect to said inner member; said inner member being imperforate throughout the length of its portion which is telescoped within said outer member; seal means between the exterior of said inner member and outer member and engaging said members to prevent leakage therebetween; the annular area of said inner member between its inner surface and its sealing diameter with said outer member being slightly greater than the annular area of said valve seat between the inner surface of said inner member and the minimum sealing circumference of said valve element with said seat.

5. In a valve apparatus adapted to be incorporated in a tubular string to be disposed in a Well bore: an upper, outer tubular member; a lower, inner tubular member telescoped within said outer member; an annular valve seat on the upper end of said inner member communicating with the interior of said inner member; a valve element carried 'by said inner member and movable relative thereto into and out of engagement with said seat; means on said outer member engageable with said valve element in response to upward movement of said outer member with respect to said inner member to shift said valve element out of engagement with said seat; means for holding said valve element in engagement with said seat; said inner member being imperforate throughout the length of its portion which is telescoped within said outer member; seal `means between the exterior of said inner member and outer member and engaging said members to prevent leakage therebetween; the annular area of .said inner member between its inner surface and its sealing diameter with said outer member being slightly greater than the annular area of said valve seat between the inner surface of said inner member and the minimum sealing circumference of said valve element with said seat.

`6. In a valve apparatus adapted to be incorporated in a tubular string to be disposed in a well bore: an upper, outer tubular member; a lower, inner tubular member telescoped within said outer member; an annular valve seat on the upper end of said inner member communicating with the interior of said inner member; a valve element carried by said inner member and movable relative thereto into and out of engagement with said seat; means on said outer member engageable with said valve element in response to upward movement of said outer member with respect to said inner member to shift said valve element out of engagement with said seat; holding means on said outer member engageable with said valve element to hold said valve element engaged with its seat upon downward movement orsaid outer member with respect to said inner member; said inner member being imperforate throughout the length of its portion which is telescoped within said outer member; seal means between the exterior of said inner member and outer member and engaging said members to prevent leakage therebetween; the annular area of said inner member between its inner surface and its sealing diameter with said outer member being slightly greater than the annular area of said valve seat between the inner surface of said inner member a-nd the minimum sealing circumference of said valve element with said seat; and spring means between and acting on said tubular members to shift said outer member downwardly with respect to said inner member to cause said holding means to hold said valve element engaged with said seat.

7. In a valve apparatus adapted to be incorporated in a tubular string to be disposed in a well bore: an upper, outer tubular member; a lower, inner tubular member telescoped within said outer member; an annular valve seat on the upper end of said inner member communicating with the interior of said inner member; a valve element carried by said inner member and movable relative thereto into and out of engagement with said seat; means on said outer member engageable with said valve element in response to upward movement of said outer member with respect to said inner member to shift said valve element `out of engagement with said seat; holding means on said outer member engageable with said valve element to hold said valve ele-ment engaged with its seat upon downward movement of said outer member with respect to said inner member; said inner member being imperforate throughout the length of its portion which is telescoped within said outer member; seal means between the exterior of said inner member and outer member and engaging said members to prevent leakage therebetween; the annular area of said inner member between its inner surface and its sealing diameter with said outer member being slightly greater than the annular area of said valve seat between the inner surface of said inner member and the minimum sealing circumference of said valve element with said seat; said outer member being spaced laterally outward from said inner member to provide an annular space therebetween; and a compression spring in said annular space engaging said outer and inner members and tending to shift said outer member downwardly with respect to said inner member to cause said valve element to be clamped between said holding means and seat.

8. In a Valve apparatus adapted to be incorporated in a tubular string -to be disposed in a well bore: inner and outer tubular members telescopically arranged with respect to each other; a valve seat on said inner member communicating with the interior yof said inner member; a valve `element movable with respect to said members into 8 and out of engagement with said seat; means on said outer member engageable with `said valve element in response to relative telescopic movement between said members to shift said valve element with respect to said seat; means for holding said valve element in engagement with said seat; said inner member being imperforafte throughout the length of its portion which is telescoped `within said outer member; seal means between the exterior yof said inner member `and outer member and engaging said members to prevent leakage therebetween; the `annular area of said inner member between its inner surface and its sealing diameter with `said outer member being slightly greater than Ithe annular area of said valve seat between the inner surface of said inner member and the sealing circumference of said valve element with saidseat.

9. In `a valve apparatus adapted to be incorporated in a tubular string to be disposed in a well bore: inner and outer tubular members telescopically arranged with respect to each other; a valve se'at on said inner member communicating with the interior of said inner member; a valve element movable with respect to said members into and out of engagement with said seat; means on said outer member engagea'ble with said valve element in response to relative telescopic movement between said members to shift said valve element with respect to said seat; 'holding means on said outer mem-ber engageable with said valve element to hold said valve element engaged with said seat; said inner member being imperforate throughout the length rof its portion which is telescoped within said outer member; seal means between the eX- terior of said inner member :and outer member and engaging said members to prevent leakage therebetween; the annular `area of said inner member between its inner surface and its sealing diameter with said outer member being slightly greater lthan the annular area of said valve sea-t between the inner surface of said inner member and the sealing circumference of said valve element with said seat.

References Cited in the le of this patent UNITED STATES PATENTS 599,603 Froclich Feb. 22, 1898 1,818,508 Scot-t Aug. 1l, 1931 2,090,055 Larson Aug. 17, 1937 2,492,694 Graham Dec. 27, 1949 2,505,410 Klaas Apr. 25, 1950 2,509,470 Baker May 30, 1950 helma-i 

